Not to be too simplistic about it, but in a broad sense, Science is about connecting with the Universe and Art is about connecting with our experience of it.
Yes, science is about finding answers and art is about expression, but there's more to it.
Both are fueled by the drive to know and to create.
Both share the goal of understanding the world by conceiving models of it.
Both create complex, nuanced models to define concepts, though the models are qualitatively different.
The models in art are intangible and implicit.
The models in science are defined and explicit.
Both use intuition and logic to test the robustness of the models.
Both want to question, both want answers, and both invite interpretation.
Art tests concepts through subjective experimentation.
Science tests concepts through objective experimentation.
Art suggests answers, but the emphasis is on leaving the questions open.
Science leaves the questions open, but the emphasis in on finding answers.
They differ in the modes of expression (artistic media vs. data) because each needs to use the language best suited to the models they've built and the tools needed to test them.
So What is SciArt?
There is no consensus definition yet, but here are some questions worth considering. Using artistic tools to do science? (eg. sonifying data) Using scientific tools to do art? (eg. GF bunny) What are the questions being asked in SciArt? Are they qualitatively different from either art or science? Maybe more about ethics? Are they a blend of both subjective and objective understanding of the world? Is the emphasis equally on questions and answers? Are the models nebulous or defined? implicit or explicit?